Rees began his rugby career with Hafod Rovers,[3] the same team that would produce fellow international teammate Dicky Owen, but switched to first-class side Swansea in 1897.

On 31 December, a telegram was received stating that Nicholls would not be able to make the first Championship game, and the Welsh Rugby Union immediately responded with news that Rees would take his place at centre, winning his first cap alongside Swansea teammate George Davies.

The Athletic News gave the Welsh victory to the pack, dismissing the threequarters, but The Sportsman wrote "an exposition of the three quarter back game was given which must have satisfied the great Mr Arthur Gould himself".

Some commentators believe that Nicholls played due to worries over his future selection caused by the good press articles the Swansea centres received.

With injuries also sustained by Teddy Morgan and Willie Llewellyn, the Welsh threequarters was hastily constructed, with Swansea's Fred Jowett, and a recalled Tom Pearson taking the wings and Rees partnering the only surviving member of the 1902 team, Rhys Gabe.

[12] On the morning of the match, Rees informed the WRU that he was ineligible to play, which would have opened the way for nominated reserve, and Swansea's captain, Frank Gordon to gain his first international cap.

[12] The WRU reacted harshly to this, and reinstated Nicholls as they believed that Rees was following club orders to give their captain an international cap.

On 21 October 1905, Rees drew his international career and any arguments of his amateur status to a close when he "Went North"; switching to professional rugby league team Hull Kingston Rovers.